In a typical processing domain, a host processor communicates with a number of end nodes through some form of interconnect. In the past, the interconnect was typically a bus (e.g., a peripheral component interconnect (PCI) bus). More recently, switching fabric has been used as an interconnection means between the host and the end nodes of a processing domain. Some examples of switching fabric technologies that may be used include 3GIO, Rapid I/O™, and HyperTransport™. In some applications (e.g., networking applications), the desire to perform dynamically distributed processing across a number of processing elements and/or redundant systems has generated a need for multiple-domain solutions. As can be appreciated, a multiple-domain system requires some mechanism for inter-domain communication. Prior techniques for providing inter-domain communication in a multiple-domain system (e.g., non-transparent bridging, multiple fabrics, flat addressing schemes, etc.) have been inadequate from a performance and/or capability standpoint. Therefore, there is need for enhanced methods and structures for providing communication between processing domains in a multiple-domain processing system.